rs121918409

Variant names:

• chr5-151851487-A-T
• rs121918409
• NM_000171.4:c.815T>A

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_000171.4(GLRA1):​c.815T>A​(p.Ile272Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GLRA1 NM_000171.4 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:2
• Conservation: PhyloP100: 9.11
• Publications: 4 publications found

Genes affected

GLRA1 (HGNC:4326): (glycine receptor alpha 1) The protein encoded by this gene is a subunit of a pentameric inhibitory glycine receptor, which mediates postsynaptic inhibition in the central nervous system. Defects in this gene are a cause of startle disease (STHE), also known as hereditary hyperekplexia or congenital stiff-person syndrome. Multiple transcript variants encoding different isoforms have been found. [provided by RefSeq, Dec 2015]

GLRA1 Gene-Disease associations (from GenCC):

• hyperekplexia 1

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• hereditary hyperekplexia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000171.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986
• PP5: Variant 5-151851487-A-T is Pathogenic according to our data. Variant chr5-151851487-A-T is described in ClinVar as Pathogenic. ClinVar VariationId is 16062.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000171.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GLRA1	NM_000171.4	MANE Select	c.815T>A	p.Ile272Asn	missense	Exon 7 of 9	NP_000162.2	P23415-2
	GLRA1	NM_001146040.2		c.815T>A	p.Ile272Asn	missense	Exon 7 of 9	NP_001139512.1	P23415-1
	GLRA1	NM_001292000.2		c.566T>A	p.Ile189Asn	missense	Exon 6 of 8	NP_001278929.1	Q14C71

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GLRA1	ENST00000274576.9	TSL:1 MANE Select	c.815T>A	p.Ile272Asn	missense	Exon 7 of 9	ENSP00000274576.5	P23415-2
	GLRA1	ENST00000455880.2	TSL:1	c.815T>A	p.Ile272Asn	missense	Exon 7 of 9	ENSP00000411593.2	P23415-1
	GLRA1	ENST00000462581.6	TSL:1	n.*573T>A		non_coding_transcript_exon	Exon 6 of 8	ENSP00000430595.1	E5RJ70

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
2	-	-	Hyperekplexia 1 (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.37
CADD	Pathogenic	32
DANN	Uncertain	0.99
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.75	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	3.7	H
PhyloP100		9.1
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-6.3	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.88		Loss of stability (P = 0.0154)
MVP		0.98
MPC		2.6
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.98
gMVP		1.0
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs121918409; hg19: chr5-151231048;